This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We have performed a series of measurements using the newly designed Bent Laue analyzer for Cu K edge XANES measurements. The analyzers consist of an Al bender system and Si (111) crystal of different thicknesses in order to provide more flux or higher energy resolution depending on their final application. We have used the selected analyzer that shows better performance in term of energy resolution, near 10 eV at the Cu K[unreadable] line energy. We have measured a set of standard samples consisting of Cu compounds of different Cu oxidation state: Cu(I) and Cu(II). These compounds were evaluated using a silicon drift detector and the bent laue analyzer. The results show that Cu(I) compounds have a very strong pre edge peak at 8983 eV where Cu(II) compounds do not have that peak. The bent laue analyzer was able to recognize the difference even under conditions of very diluted samples. We have also evaluated the Cu content of tissue sections: normal and tumor tissue. The tumor data indicates that Cu(II) species are potentially present in the tissue while the normal tissue data indicates very little or no content of Cu(II) species. These results will be evaluated considering other complementary technique to confirm the presence of Cu(II) in tumor tissue sections.